This invention relates to solar panels and apparatus for manufacturing the same.
Ever-increasing concern for the development of new sources of energy has led to a considerable re-examination of the possibility of utilizing solar energy for heating purposes. Typically, the various proposals made for this purpose utilize solar panels backed by a heat absorbing medium through which a fluid may be circulated to convey heat absorbed from solar energy passing through the solar panel to a point of use.
In general, it is desired that the solar panel act as check valves for solar energy, allowing its passage to the heat absorbing mediums while precluding the flow of energy from the heat absorbing medium through the solar cells. Many of the solar cell constructions heretofore proposed are quite inefficient in so acting. A great deal of the energy entering the solar cell is either not conducted to the heat absorbing medium or, if conducted to the heat absorbing medium, is lost through convection, conduction and radiation. Such cells, therefore, are unsuitable for extensive use and, where usable at all, are limited to placement in areas having relatively mild climates.
Other, more efficient cell constructions have been proposed and, on a pilot basis, have operated quite satisfactorily. Such cells typically reduce losses due to convection to an absolute minimum and minimize radiation losses due to the emittance of infrared radiation from the absorbing medium. Materials with which such cells are formed typically are poor conductors, with the result that the conduction losses are also minimized.
However, the use of such cells has not, to date, proven economically feasible on a large scale basis due to the fact that exacting manufacturing procedures are required to construct such cells in a way to minimize convection, reradiation, and reflection losses.